Rocking bed and cam control mechanism



F. A. BLASHFIELD ROCKING BED AND CAM CONTROL MECHANISM Dec. 2, 19258v 5Sheets-Sheet 1 Filed Oct. l5.- 1955 TTRNEY Dec. 2, 1958 F. A. BLASHFIELD2,862,392

ROCKING BED AND CAM CONTROL MECHANISM Filed Oct. 15 953 5 Sheets-Sheet 2IN V EN TOR.'

ATToRNns.

De. 2, 1958 F. A. BLASHFIELD 2,862,392

RooxING BED AND CAM CONTROL MECHANISM 5 Sheets-Sheet 3 Filed 001.. 15.l953 WI l INVENTOR.'

QT y@ M/@a @JMW ATTORNEYS.

De 2 1958 F. A. BLAsHFlELD 2,862,392

' RocKING BED AND CAM CONTROL MECHANISM Filed Oct. 15, l953 5Sheets-Sheet 4 1N V EN TOR.'

ATTURNEYS.

DeC 2, 1958 F. A. BLASHFILD 2,862,392

ROCKING BED AND CAM CONTROL MECHANISM Filed Oct. l5. 41953 5Sheets-Sheet 5 QU f1 IN V EN TOR.'

. 2,362,392 j RocKiNG BED AND CAM coNTRoL MECHANISM Y, i

VFloyd A. Blashield, Evanston, Ill., assigner to American .HospitalSupply Corporation, Evanston, lll., a corporation of Illinois Y Y ThisVinvention relates to a rocking bed and cam control mechanism. The .camcontrol mechanism is useful in connection with the control of therocking movement of the bed, -btt is also obviously useful Vin theycontrol of other structures and elements or devices to be moved.

A primary object of the invention is to provide in connection with themoving of a rocking bed or other type of device, .means for changing theamplitude of movement of the bed -or device during the operation of therocking or moving mechanism, thus making it unnecessary to stop themotor to effect a change in the amplitude of movement or throw of thecam. A further object is to provide means whereby a device may beactuated by a cam while at the same time providing simple crank orhandle means whereby Vthe position of the cam may be changed to alterits throwwhile the operating mechanism y '2,862,392 iatented Dec. 2,A1958 lCC Fig. 5; Fig. 7, a broken, part-sectional view showing the:clutching mechanism and locking mechanism employed;

Fig. 8, a part-sectional detail view of the worm driven by the handlecrank; Fig. 9, a perspective view of the chain of geariconnectionsbetween the handle crank and the cam member; Fig. 10, a broken,vertical, part-sectional View of a modified form of structure in which amotor is employed for adjusting the position of the cam rather than themanual means shown in Figs. l to 9; and Fig. 11, a side view of thestructure shown in Fig. l0.

Referring more particularly to Figsfl and 2, the general arrangement ofthe structures will be described, it being understood that whilereference is made in particular to the rocking bed shown, such bed ismerely illustrative of a number of devices with which the cam controlmechanism may be employed. In Figs. l and 2, 1t) designates the baseequipped with casters 11 and providing a support standard or frame 12.Upon the top of the frame 12 is supported a rock shaft 13. A bed frame14 is in fulll operation. A still further object is to provide a Idevice whereby a crank shaft is utilized for rotating a cam having itsperipheral portions encircled by a ring and the ring connected to thedevice to be moved, while at the same time utilizing the Acrank shaftfor supporting a member secured to the cam, connections. being providedVfor moving said member to swing the, cam to different effec-v tivepositions upon the crank shaft. Yet another object is to provide arocking bed, or the like, equipped with a driven crank and a cameccentrically receiving the crank anda ring freely'receiving theperipheral portions of the cam and .connected to the bed` at one side ofits rocking center, means being provided for rotating the camindependently of the operation of the crank for changing the position ofthe cam thereon. A further object is to provide in connection with theforegoing handle-mechanism supported in line with the driven shaft ofthe crank for eifecting such changein the position `of the cam. Yet

another object is to provide motor-driven means for opin the setposition by such worm and wormV gear, etc.

Other specic objects and advantages will apstructures. pear as thespecification proceeds.

The invention is shown, in illustrative embodiments, by the accompanyingdrawings, in which- Figure l is a perspective view of a rocking bedequipped with cam control mechanism embodying my invention;

Fig. 2, a broken side view in elevation, the bed being shown in a tiltedposition by dotted lines; Fig. 3, a vertical sectional view, on anenlarged scale, of the crank, .cam mechanism, and the control mechanismtherefor; Fig. 4, a plan sectional view of the structure shown in Fig.3; Fig. 5, an enlarged, brokenside view inelevation of the cam-operatingmechanism; Fig. 6, a broken sectional view, the section being taken asindicated at line 6--6 of "with the driven shaft 30, no rocking of thebed will is supported upon the shaft 13 and carries a mattress 15.

If desired, the bed frame 14 may be provided with sectional framesadjustable by means of the links 16. The links 16 are fixed tothe largegears 17 mounted on one side ofthe bed and operated by means of handledriven worm and gear connections. By this means, the bed sections, whenmoved into the desired position, will remain fixed in such positionwithout further attention because of `theworm and gear structuredescribed.

The standard 12 may be provided with a Xed pointer 18 and a scale 19fixedto the rock shaft 13 and provided with graduations which will thusindicate the degree of tilting of the bed at any moment. k

The mechanism for rocking the bed will now be described.

Fixed to the bottom of the bed frame are the bearing members 20. Withinthe mountings V20 is supported a rock member 21 supporting a controlshaft 22 and having a bevel gear engaging the vertical bevel gear 22a.The vertical bevel gear 22a is carried by a screw 23 which enters athreaded socket member carried'by the frame member 24. The frame member24 extend on opposite .sides of an ear 25 carried by a cam ring 26. Thecam Vring 26 freely receives a cam 27 eccentrically supported upon thecrank shaft 28. The crank shaft 28, as will be shown more clearly inFig. 6, is rigidly carried by a crank arm 29 Xed to a driven shaft 30. y1 f y Any. suitable means may be provided for driving the shaft 30. Inthe specific illustration given, there is provided a motor 31 drivingthrough speed-reducing gears 32 a pulley 33, and, by means of the belt34, another pulley 35. The shaft upon which pulley 35 is mounted drivesthrough reducing gears 36 the drive shaft 30.

yThe cam and ring mechanism may be of any suitable construction. Asshown more `clearly in Fig. 6, the cam 27 is in the form of a dischaving an eccentric mounting 37 receiving the crank shaft 28. Betweenthe cam 27 and the ring 26 may be interposed antifriction bearings 38.The straps 24 are provided at their lower ends with ears 39 centrallyapertured at 40 to receive the locking pin 41. As shownmore clearly atthe top of Fig. 5, the pinv'41y extends through the ears 39 and thecentral lug 25 carried by the ring 26 so as to secure the ring 26 thusto the straps 24, which in turn are connected by the `screw 23 to therotatable member 21 on bed 14.'

The ring 26 is confined about the peripheral portion of the cam 27 andtheA antifriction bearings 38 carried thereby by means of a locking discor band 42, the band 42 being held in Yposition by the screws 43, asshown more clearly in Fig. 6. f

Assuming that the parts are -in the position shown in Fig.. 6 with theVcenter of the cam 27 in alignment freelyreceive the shaft 28.

occur when'the shaft 30 is driven because the crank `shaft '28 will'rotate about theV true center'of'the cam27 and the center of cam27=.will be in line with the axis of shaft 30. However, if the cam berotated in either the `bed will occur and the-ring structure"26will'begin to rise and fall. -Iffthere'forq means can'beprovided forshifting thel positionY of the -cam 27 throughV` mech- Vanisrnv thatmaybe Voperated while theidrivenshaft '3% Lis in operation, a change inamplitude'of the rocking movement of thebed `can be electedwithoutrequiring Vthe stopping of `the motor.

I will now describe the mechanism for changing the positionv of thecam'27 while the motor is in operation. v

The cam control mechanism-shownin the drawings employs rst a gear 44,'which is apertured centrally to i VThe Vgear '44 which thus may operateindependently of shaft 28,'isbolted directly to the cam 27,employing'three bolts 45. `Thus,"when the gear 44 is rotated, itrequires-a similar movement of cam 27 and the cam 27'may'be'thus causedto move in a circular path aboutthe shaft 28 and thuseto'vary the throwof the cam.

Gear connections are provided for rotating the large gear 44 which hasbeen described as bolted directly to the cam 27. For the Apurpose `ofclarity, I`have Vshown such gear connections in Fig. 9. It will be notedthat a pinion -gear 46 meshes with the large gear 44 and is fixed uponva shaftl 47 carrying a worm gear 48. The worm gear 48 `meshes with` aworm 49 on shaft 50. The shaft 50 carries a bevel gear 51 meshing withanother bevel gear 52 Acarried by shaft 53. The shaft 53, throughseveral clutch connections, is connected to a handle on crank 54. Thus,when the handle 54 is turned with the clutch ends so as to rotate shaft53, there isa rotation of gears 52,51, 49, and finally pinion gear 46meshing with the large gear 44 which is bolted tothe cam 27. By thismeans, the cam 27 may be rotated manually through the rotation of thehandle or crank 54 to change the setting of the cam 27 and thus vary itsthrow. Such change of `the cam is Veffected without requiring thestopping of the motor and while, in fact, the motor is in fulloperation.

The clutch and locking mechanism is important for the following reason.InV the Aoperation of the crank shaft, resulting in movement of theparts, there is found to be some slight creeping ofthe adjustment partsor gears, and'while such change is extremely small, over a substantialperiod of timethere may be a decided change in the amplitudeofthe-movement of the cam away from the desired setting. lTo Vavoidthis, I provide a locking mechanism-and clutch mechanism which willnow'be described.

Asshown-more clearly in Fig. 3, I provide'within the casingSSithe-xedshafte56=having a depending fixed support'f57. YYThe fixed support 57 isshown with`the clutch mechanism parts LVAbest in'Fig. 7. observed'fthatthe fixed part57` is provided with a recess 58 adapted to receive alocking pin59 threadably received within theAslidable memberl60. A ringmember 61 is Vrfixed to the shaft 53 by means of vpinl 62, yand isaperktured at v-63 to receive the outer free end-of-pin`59- 5Acompression spring-64 is received within oppositerecesses in the members-60 and 61 so as to ordinarily Vurge "the memberv 60 toward the fixedabutment or support -57. It will be observed that thememberO has asubstantial portion projecting outwardly Vbeyond the abutment 57 soasyto permitit to beengaged and movedrinwardly Vto* retract the pin 59from the recess 58. vThe handle orV crankf54-is tiXed to a sleeve 65,and the sleeve 65,*

having running shaft66a, isA provided'at its inner end with a clutchtongue. 66 adaptedfto" engage a clutch'in shaft'53. vA .lightsp'ring 68may be employed tomaintain the sleeve 65 spaced from'the vmember 60, andin n will be Y the illustration given, the spring 68 extends between theIn operating the clutch, lthe crank handle 54 is moved inwardly to bringthe end of the sleeve into engagement with the slidable member 60 and asthe member 60 is pressed inwardly, the locking pin 59 is detached fromthe recess 58, thus permitting the shaft 53 to be freely rotated,andewith the squared tongue 66 engaging the squared recess 67, rotationof-shaftl 53 is readily effected.

It is desired to provide means for indicating the position of thecamafter it hasbeen moved and thus to determine the amplitude ofmovement. To.y accomplish this, I provide the casing 55 on its outerside with a circular scale70 andV provide a pointer 71 lfor cooperationtherewith. The pointer 71, as shown more clearly in Fig. 7, is mountedupon a disc'72 secured by the setscrew 73 to a hub member 74 freelymounted upon shaft 53. The hub member 74 is equipped at `its inner endwith a gear"75which,"in turn, meshes with a gear 76 freely mounted bythepin 77 upon the end'of the shaft-28.

Fixed-to the gear '76 is a roller 78 connected by a strap 79 to thelarge gear 44 bolted to .the cam 27. As shown more'clearly in'Fig. 6,the bracket 79tis secured by a threaded-pin 80 to an inner portion ofthe gear 44. with this structure, when the .gear 44 is rotated, there isproduced'a corresponding rotation of the gearv 76 on shaft-28 and gear75 on the hub '74, thus producinga rotation ofthe pointer'71 in linewith the graduations on scale70.

Y Operation -a fixed crank arm 29. and thereby drives the crankshaft 28.

The cam disc or wheel-27 mounted eccentrically upon crank shaft28rotates to raise and lower the cam 27, depending upon the position ofthe cam. As the cam V27 rises and falls with-the rotation of thecrankshaft 28, the sleeve or ring'26 similarly rises and falls, carrying withit the ear 25y and thereby the metal straps .24 and the screw 23, thustransmitting` the movement to -the bed 14 there-above and rocking thebed.

The shaft 53v is concentric with shaft 30, and as gear -44 gyrates, gear46, which is in -mesh therewith,4 also gyrates.

The casing 55 andeverything contained-and attached therewith rotates.When the cam is rotated yso -as to bring the-center ofthe cam in linewith the drive shaft i310, as described in column 3, no longitudinalmovement of the connecting link 26 is effected and there 'is no rockingof the-bed. VHowevenfas the cam is rotated in either direction upon theshaft 28 so as to 'bring the center of the cam off-center with respectto the driven shaft 39, rocking of the bed 'occurs and to effect thischange, the handle may be'operated in either direction.

To change the position of the cam so as to vary its throw,v the operatornew rotates Athe handle 54, after `pressing it 4inwardly so as toree'the member 60 and the pin 59 from the recess-158 and; toy bring theclutch parts -66andl 67 into engagement. By this means, shaft 53 isrotated and thence throughv gears 52 and 51, shaft 56, worm 49, wormgear 48,- shaft 47, and pinion 46,

`:the large gear ".44 which isbolted` to the cam 27 isA rotated. Thiscauses the cam 27 to move bodily about the crank shaftZS to any selectedposition. Such move- Vment is accomplished during 'the rotation of thecrank shaft.28.and without affecting the regular operation ofethf'rmotor and the driven shaft 30. Simultaneously, with any shiftingofthe position` of: the cam, there is .pro

'duced .through the` connector strap 179 a shifting of the free gear 76and thereby the gear 75 and hub 74 carrying the pointer disc 72.

While, in the foregoing, I have described a manuallyoperated control forshifting the position of the cam, it will be understood that other meansmay be provided for effecting such change. If desired, a motor may beprovided for this purpose and instead of the nurse having to benddownwardly to operate the manual crank, the change may be effected bysimply throwing a switch button located at a convenient point on the bedand thus operating a motor to increase or decrease the amplitude of therocking movement. In Figs. and l1, I have shown such motordriven means,and since the parts are to a large degree the same in these gures asthose shown in the preceding figures, it will only be necessary to referto the added parts.

In Figs. 10 and l1, there is shown a motor 81 which drives, throughreducing gears within the casing 82, a shaft 83 carrying a bevel gear84. Meshing with gear 84 is another bevel gear 8S, and through the chainof gears shown there is driven the Worm 49a, worm gear 48a mounted onshaft 47a, and thereby through a pinion the large gear 44a which isbolted to the cam 27a.

In the operation of the structure shown in Figs. 10 and 1l, the motordrives through the chain of gears shown the large gear 44a and operatingexactly as the gear 44 heretofore described, produces a rotation of thecam 27 about the crank shaft to change the throw of the cam.

While the structure has been described in connection with a rocking bed,it will be understood that the mechanism is applicable to a greatvariety of machines in which an oscillating or reciprocating movement isdesired or other movements which may be effected by a cam as described,and the cam control mechanism herein described may be effective for thecontrol of such machines. The use of a hospital bed as an illustrationof the use of the cam control mechanism is desirable because of theeffectiveness of such control in connection with a hospital bed, wherebya patient will not be disturbed in the operation of the mechanism, thechange of amplitude of movement being effected without stopping themachine; however, it will be understood that the illustration is notlimiting in character but merely sets forth one of the many deviceswhich may be used in connection with a cam control mechanism.

While, in the foregoing specification, I have set forth specificstructures in considerable detail for the purpose of illustratingembodiments of the invention, it will be understood that such details ofstructure may be varied widely by those skilled in the art withoutdeparting from the spirit of my invention.

I claim:

1. In element-moving mechanism, a frame, a driven y shaft mountedtherein, a crankshaft fixed to one end of said driven shaft and havingits axis in spaced parallel relation thereto, a cam member having aneccentric mounting receiving said crankshaft and having its centeralignable with said driven shaft, a ring freely receiving the peripheralportions of said cam, connecting means between said ring and saidelement to be moved, control means rotatably supported in generalalignment with said driven shaft but longitudinally spaced therefrom, arotatably mounted handle, said handle 'and' control means being normallyunconnected for independent rotation of said control means withreference to the handle, and selectively operable kconnecting meansbetween said handle and said control means for locking said controlmeans and handle against independent rotation, whereby, said 6 handlemay be connected with said control means by said second-mentionedconnecting means for rotation of said cam upon said crankshaft withoutinterrupting rotation of said drive shaft.

2. In element-moving mechanism, a frame, a driven shaft mounted thereon,a crankshaft actuated by said driven shaft, a cam member aperturedeccentrically to receive said crankshaft and having its center alignablewith said driven shaft, a ring freely receiving the peripheral portionsof said cam, a gear apertured to receive freely said crankshaft andfixed to said cam, rotatable control means independent of saidcrankshaft and longitudinally spaced from said driven shaft for rotatingsaid gear to change the position of the cam thereon, and a rotatablehandle selectively and axially movable between a normal inoperativeposition wherein said handle is freely disengaged from said controlmeans and an operative position wherein said handle engages said controlmeans for rotation of said cam upon said crankshaft as said handle isturned, said handle being movable into its operative position forchanging the position of said cam while said driven shaft is beingrotated.

3. In element-moving mechanism, a frame, a driven shaft member mountedthereon, a crankshaft carried by a crank arm on the driven shaft, a cammember apertured eccentrically to freely receive said crankshaft andhaving its center alignable with said driven shaft, a ring freelyreceiving the peripheral portions of said cam, connecting means betweensaid ring and said element to be moved, rotatable control meanslongitudinally spaced from said driven shaft for turning said cam'tochange its position upon said crankshaft, and a rotatable handleselectively and axially movable between a normal inoperative positionwherein said handle is freely disengaged from said control means and anoperative position wherein said handle engages said control means forrotation of said cam upon said crankshaft as said handle is turned, saidhandle being movable into its operative position for changing theposition of said cam while said driven shaft is being rotated.

4. In an element moving mechanism, a frame, a driven shaft mountedthereon, a crank shaft xedly secured to one end of said driven shaft andhaving its axis in spaced parallel relation to the axis of said drivenshaft, a circular cam member apertured eccentrically to rotatablyreceive said crank shaft, a ring freely receiving the peripheral portionof said cam member, a gear centrally apertured to receive freely saidcrank shaft and fixed to said cam member, a control shaft operativelyassociated with said gear for rotating the same upon said crank shaft,and actuating means normally disengaged from said control shaft butbeing movable into an engaged position therewith for rotating saidcontrol shaft and for thereby rotating said cam member upon said crankshaft, said actuating means being movable between engaged and disengagedpositions while said driven shaft is being rotated.

References Cited in the le of this patent UNITED STATES PATENTS 421,297Mills Feb. 11, 1890 540,394 Leitch June 4, 1895 1,700,966 Baerbalck Feb.6, 1929 2,036,625 Garratt Apr. 7, 1936 2,241,378 Evans May 13, 19412,242,715 Woodford May 20, 1941 2,445,258 Beem July 13, 1948 2,592,237Bradley Apr. 8, 1952 2,696,207 Bushnell Dec. 7, 1954

